Method of building of tires



Oct. 26, 1943. J. c. CARLlN 2,332,987

METHOD OF BUILDING 0F TIRES Filed Nov. 19, 1940 on the collapsible tire building Patented Oct. 26, 1 943 METHOD OF BUILDING F TIRES James C. Carlin, Norristown, Pa., assignor to Lee Rubber & Tire Corporation,

Conshohocken,

Pa., a corporation of New York Application November 19, 1940, Serial No. 366,216

8 Claims,

corded fabric, with the requisite amount of rub-.

her. This fabric is thereafter bias cut and the bias cut strips are thereafter fed to the tire building drum where such strips are compacted and otherwise treated in the formation of the tire carcass. This laminated cord fabric structure is immediately thereafter covered with the tire tread to complete the tire carcass. The tire building drum has associated therewith devices such as stitching rolls which operate upon the strips of cord fabric as they are applied to the tire building drum and these stitching rolls also operate upon the tread after the same is applied to the drum. Other operations are also performed upon the fabric and tread while they are drum. r

In the building of such tires or tire cores it is customary practice to make the cord plies of such length that when they are placed around the drum the ends thereof overlap slightly. By reason of the increased diameter of the surface of the drum as the plies are applied thereto the successive plies have to be longer than the preceding plies. Moreover, the several plies of cord fabric employed in the building of a tire are not always of the same width for the reason that the longitudinal marginal portions of the plies are turned over the bead units to overlie and envelop the latter to retain them in place, the several plies employed in the construction of a single tire carcass being turned inwardly to varying extents in order to insure that the intumed edges of the several plies are not so coincident as to form a pronounced shoulder or ledge within the tire side wall.

In the factory, the manufacture of the fabric is essentially a continuous process, whereas the tire building process is discontinuous and relatively slow as compared with the rate of manufacture of the cord fabric. Moreover, one calender is capable of supplying fabric at a rate adequate for the needs of a large number of tire building drums. For these and for other reasons, the temporary storing and transportation of the cord fabric to the tire building drums constitutes a problem which prior to the present invention has been inadequately met in that the means provided therefor were costly, clumsy, consumed an excessive amount of factory space, and also consumed an excessive amount of time and labor in their manipulation. It is'therefore the aim of the present invention to provide a process of tire manufacture in which these diificulties are substantially minimized, and in which the bias cut fabric strips of the necessary different widths may be stored for subsequent use with a minimum consumption of time and labor and also in a minimum space.

. In the prior practice, the feeding of bias cut cordstrips to the tire building drum was largely, if not entirely, a manual operation which considerably reduced the efiectiveness of the tire building drum and generallyv slowed the tire building process. It is therefore oneof the objects of the present invention to provide for a more or less automatic feeding of the tire strips to the drum.

More comprehensively stated it is the aim of the present invention to provide a method and means for the treatment and storing of cord fabric in such manner and form that it maybe substantially automatically fed to a tire building drum and thereby reduce the manual operations at the building drum to a minimum with a consequent increase in the efficiency of the tire building drum and also with a consequent improvement in the quality of the tire.

In order to accomplish the foregoing ends the present process provides for winding up a multiplicity of bias cut strips of cord fabric in the form of rolls by means of a carrier fabric; the strips being disposed on the carrier fabric in end-to-end fashion. This roll is subsequently employed for feeding the strips to the tire building drum. The strips are disposed on this carrier fabric in the correct order and manner in which they are to be fed to the tire building drum. Thus for this purpose the bias cut strips are disposed with their longitudinal edges parallel to the edges of the carrier web and preferably with the adjacent bias cut ends of two adjacent strips disposed angularly to each other. In addition the longitudinal center lines of the strips are all in alinement so as to provide for the accurate feeding of the cord strips to the drum. The strips are disposed on this carrier web in groups, each group comprising the number of strips employed in the building of the tire carcass, each of the strips in each group being properly dimensioned, that is being of the proper length andwidth for its particular position. on the drum. Thearrangement of such groups and employed in the present invention.

strips within each group is such that when the roll is unwound the strips are fed to the tire building drumin their proper order and in propconsists in the manufacture of the cord fabric in the form of an endless web. This is accomplished on a calendering machine and the endless web of cord fabric produced by the calendering machine may be bias cut as it leaves such machine or it may first be wound into a roll and be bias cut subsequently. Either of these methods of handling or treating the fabric may be In Figure 1 reference character l may therefore be said to designate the calendering machine with the core fabric i i produced thereby passing out of the machine, or the reference character In may designate a roll of previously produced cord fabric which is being unwound and fed to the bias cutting machine l2. Such bias cutting machines are common in the art and need not be specifically described herein. The cutter i3 operates periodically to cut the fabric H into strips M. As shown in Figure 1 such strips i i are of equal width. In a modification of the present process which will be described in a later portion of this specification, the width of the strips M is varied in accordance with the needs of the tire which is to be produced. In the form of the invention at present being described, however, such strips it are of equal width. The strips M will adhere to each other because the rubber is still in a tacky condition and the strips there= fore still approximate to a degree the condition of continuous web of fabric. The strips in this condition are received by a carrier web l5 which moves at the same rate or in step with the movement of the fabric M. The carrier web it together with thestrips M is rolled into a roll it.

The bias cutting machine i2 may be operated so as to cut the bias strips of any desired width by varying the rate of travel of the web H or by varying the period of operation of the cutter it. For the purpose of the present invention,

several rolls it, ill and D8 are produced, each comprising a carrier web 95 and a multiplicity of strips of cord fabric it carried thereby, the width of the strips, however, in each roll differing from the width of the strips in the other rolls. The number of such 'widths may diifer, depending upon the specific construction of the tire and the specific method of its manufacture; it is found, however, that the more common practice involves the use of three widths of strips.

The next step in the present process involves the formation of a-feed roll of such strips. For this purpose three rolls such as it, H and i8 shown in Figure 2 of the drawing are unrolled in a manner which permits the manual removal of a strip at a time from each of the webs in suitable order and depositing each strip on the travbuilding drum 3Q.

elling web 30. For this purpose it is preferred to unwind the rolls l6, l1 and I8 in a stepwise manner and independently each of the other.

For the purposes of illustration we may assume that the tire we are seeking to manufacture contains a four-ply carcass and that such carcass comprises two strips of the same width, a third strip of another width and a fourth strip of still another width. In order that in the subsequent feeding of the strips to the tire building machine such strips should be fed in the proper order when the feeding roll is unwound, the strips in each group have to be deposited on the carrier web 30 in the reverse order from that in which they are to be fed to the tire building drum. In the diagrammatic showing of Figure 2, roll l6 carries strips M of the first width, roll I! carries strips I 9 of the second width and roll it carries strips 20 of the third width. Thus a group of four strips consisting of two strips i ll, one strip i9 and one strip 20 are needed for each tire core.

Each strip after it is removed from the roll Hi, If or iii and before it is deposited on the carrier web 30 is first adjusted to its proper length. The fabric of which these strips are made is easily severed by a simple manual operation. The operator therefore merely measures the desired length of each strip and removes any excess of the strip at one end thereof. He then deposits the strip on the travelling web 30 and deposits each successive strip after it has been measured and cut for length, taking care that the longitudinal center lines of the strips are in aline- .ment. In order that the feeding of these strips to the tire building drum should be facilitated, the adjacent strips are deposited on the carrier web 30 in the manner shown with the ends thereof disposed angularly to each other and providing a slight overlap at the corners as shown at 3 I This overlap greatly facilitates the feeding of each group of strips to the tire building drum. The carrier web 30 together with the multiplicity 0% groups of strips is wound to form a feed roll 3 Turning back to the unwinding of the rolls it, I? and i8, it will be observed that the carrier fabrics El, 22 and 23 of such rolls are rewound into empty rolls 2d, 25 and 25. The fabrics M, 22 and 23 are made to travel in a direction at an angle to the direction of travel of the strips Ml, i9 and 20.

Figure 3 illustrates the tire building step employing the feed roll 33 and feeding the fabric strips to the building drum 35. In this operation the feed roll 33 is unwound, carrier web Bil is wound onto roll 35 while the strips of tire fabric travel on guide 35 and onto the tirebuilding drum 38. The overlapping portions shown at 3i serve to draw the strips successively onto the guide 36 and to deliver the same to the tire At the same time the overlapping is so small that it does not interfere with the manual separation of the strips in order to permit the stitching rolls 3'! to operate upon each of the strips successively while the feeding of the other strips is interrupted.

It will now be understood that by means of the present invention and by means of the process thus far described, 'any desired number of rolls of strips of different widths may be stored until it becomes necessary to'build-tires of a known design. At such time the rolls such as rolls it, ii and it are unwound and their strips distributed to form feeding rolls which again may be stored and made available for subsequent use in the building of tires on the tire drum. Aside from the fact that such rolls may be stored in the minimum of space and that the same can be transported in the plant with great facility, the actual tire building operation on the tire building drum is greatly facilitated by the automatic feeding of the strips to the drum and is further facilitated by the elimination of strip books and racks which, prior to this invention had occupied considerable space immediately adjacent the tire building drum and had necessitated much time and labor in their manipulation during the tire building operation.

' Under some conditions, the said roll 33 with the proper distribution of the four strips thereon may be obtained directly from the cutting machine 50 shown in Figure 4. For this purpose the cutting machine would be operated so as'to cut strips of variable width from the same web of fabric l I. For example in the present case the cutter would operate to cut in succession the strips I4, l9, M and 20, and this series of operations would repeat itself so as to provide a bias cut web in which the strips fall in groups of four, each group comprising the proper arrangement of strips of the desired width for the tire which is about to be built. The traveling web would be disposed adjacent to the delivery end of the cutting machine and the strips would be removed one at a time, adjusted to length, and'deposited on the carrier web 5| so as to form the feed roll 33 shown in Figure 2.

As is shown in Figure 1, the cord fabric is conventionally made with the rubber impreghated cords thereof extending in parallelism, these cords being cut through at a bias to form the separate strips l4 each made up of parallel cords impregnated with and held together with rubber. Also, as is well known in the art, it is the conventional practice in forming the tire carcass that v the several cord fabric strips or plies thereof are arranged in superposed relation to form a laminated foundation structure or core of the requisite thickness, each strip or ply being so disposed that the cords thereof extend at a bias or angularly across the tire carcass body. Moreover, in accordance with conventional practice, the several plies or strips are relatively so arranged that cords of one ply extend angularly with respect to the cords of the next adjoining ply, in view of which the several plies or strips which make up a single series thereof, such as the plies ll-|4 Iii-40 of Figure 2, are relatively so arranged that the cords of a given ply extend angularly with respect to those of the next succeeding ply in the series.

In view of the fact that cords are held together simply by the impregnating rubber, it becomes a simple matter to adjust each ply to required length merely by the expedient of severing the ply fabric at any point in the length thereof through separation of the cords at that point.

What is claimed as new and useful is:

1. The method of preparing and handling cord fabric plies for use in'building a tire core comprising'the steps of forming several series of bias cut-strips of ply fabric of different widths, depositing the strips longitudinally on a carrier web each behind the other with their longitudinal center lines in substantial alinement, the strips forming a plurality of groups, each group comprising at least one strip from each series, then winding said carrier into a. roll with the ply fabric strips disposed between" the convolutions of said roll, and thereafter feeding the strips to a tire building drum in groups.

2. A method of preparing and handling cord fabric plies for use in building a tire comprising the steps of forming a plurality of rolls of a carrier web and strips of ply fabric for a tire core, the strip widths varying between rolls, unwinding a plurality of such rolls, removing the strips of ply fabric therefrom in a suitable order, while rewinding the carrier web for subsequent use, trimming said strips, to the desired length, and depositing said strips in suitable order on another carrier web, the strips being deposited thereon lengthwise of said other carrier web with their longitudinal center lines in substantial alinement and providing a roll having a plurality of groups of strips each group comprising several strips of fabric disposed in the order in which they are to be applied to a tire building drum; and thereafter unrolling the last-mentioned roll, whereby to successively expose the strips for delivery in seriatim to a tire building drum. I

3. A method of preparing and handling cord fabric plies for use in building a tire comprising the steps of forming a plurality of rolls of strips of ply fabric and a carrier web, the strip widths varying between rolls, unwinding the rolls, selectively removing the strips of tire fabric therefrom in a suitable order, while rewinding the carrier web for subsequent use, and depositing said strips on another moving carrier web with the ends of adjacent strips disposed angularly to each other, winding the same to provide a roll having a plurality of groups of strips each group comprising several strips of fabric requisite for forming a tire core, and thereafter unrolling the last mentioned roll whereby to successively expose the strips for delivery in seriatim to a tire building drum.

4. A method of preparing and handling cord fabric plies for use in building a tire comprising in the first stage the steps of forming a plurality of bands of ply fabric, bias cutting the same into strips, the width of the strips in each band being uniform but differing from the width of the strips in other bands, superposing each band on a continuous carrier web and forming a roll thereof; further comprising in the second stage the steps of unwinding a plurality of such rolls having strips of different widths, removing the strips of tire fabric therefrom in a suitable order, while rewinding'the carrier web for subsequent use, and

- depositing said strips in suitable order on another moving carrier web, the strips being deposited thereon lengthwise of said other carrier web with the ends of adjacent strips disposed angularly to each other and having their meeting comers slightly overlapping, and winding the same into a roll, thereby providing a plurality of groups of strips each group comprising several strips of fabric disposed reversely to the order in which they are to be applied to a tire building drum; the third stage comprising the steps of unrolling the last-mentioned roll whereby to successively expose the strips for delivery in seriatim to a tire building drum while rerolling the carrier web for subsequent use.

5. A method of preparing and handling cord bands of ply fabric, bias cutting the samev into strips, the width of the strips in each band being uniform but differing from the width of the strips in other bands, winding each band together with a carrier web and forming a roll; further comprising in the second stage the steps of unwinding a plurality of such rolls having strips of diiierent widths, removing the strips of tire fabric therefrom in a suitable order, trimming said strips to the desired length, and depositing said strips in suitable order on another moving carrier web, the strips being deposited thereon lengthwise of said other'carrier web with the ends of adjacent strips disposed angularly to each other and having their meeting corners slightly overlapping, and forming the same into a roll having a plurality of groups of strips each group comprising several strips of fabric disposed reversely to the order in which they are to be applied to a tire building drum; the third stage comprising the steps of unrolling the last-mentioned roll whereby to successively expose the strips for delivery in seriatim to a tire building drum while rerolling the carrier web for subsequent use. v

6. A method of preparing and handling cord fabric plies for use in building a tire comprising in the first stage the steps of forming a plurality of bands of ply fabric, bias cutting the same into strips, the width of the strips in each band differing from the width of the strips in other bands, winding each band together with a carrier web and forming a roll; further comprising in the second stage the steps of unwinding a plurality of such rolls, removing the strips of tire fabric therefrom in a suitable order, while rewinding the carrier web for subsequent use, and depositing said strips in suitable order on another carrier web, the strips being deposited lengthwise of said other carrier web with each strip equally spaced from the edges thereof and Winding the same into a roll thereby providing a, plurality of groups of strips each group comprising several strips of fabric disposed in reverse to the order in which they are to be applied to a'tire building drum; the third stage comprising the steps of unrolling the last-mentioned r011 whereby to successively expose the strips for delivery in seriatim to a tire building drum while enrolling the carrier web for subsequent use.

7. A method of preparing and handling cord fabric plies for use in building a tire comprisingv in the first stage the steps of forming a plurality of continuous bands of rubber impregnated tire fabric, bias cutting the same into strips, the width of the strips in each band being uniform but differing from the width of the strips in other bands,-

superposing eachband of cut strips on a continuous carrier web and formin a roll thereof; further comprising in the second stage the steps of simultaneously unwinding a plurality of such rolls having strips of different widths, the number of such rolls corresponding to the number of ply widths required for the tire, removing the strips of tire fabric therefrom in a suitable order, while rewinding the carrier web for subsequent use,

trimming said strips to the desired length, and

depositing said strips successively in suitable order on and lengthwise of another moving carrier web, the strips being deposited thereon with their longitudinal center lines in substantial alinement with the ends of adjacent strips disposed angularly to each other and having their meeting corners slightly overlapping, and winding the same to provide a roll of carrier material carrying a plurality of groups of strips, each group comprising the requisite number of strips of tire fabric disposed in reverse to the order in which they are to be applied to a tire building drum; further comprising in the third stage the steps of unrolling the last-mentioned roll whereby to successively expose the strips for delivery in seriatim to a tire building drum while rerolling the carrier web for subsequent use.

8. The method of preparing and handling cord fabric plies for use in building a tire comprising the steps of bias cutting a web of tire fabric into a plurality of groups of strips each group comprising the requisite number of strips of assorted widths, depositing such strips on a carrier web longitudinally thereof one behind the other with the ends of adjacent strips disposed angularly to each other and with overlapping corners, and winding the carrier web strips into a feed roll, thereafter unwinding the roll, whereby to' successively expose the strips for delivery in seriatim to a tire building drum, and rewinding the carrier web.

JAMES C. CARLIN. 

